Freescale Semiconductor i.MX 6DualLite, Справочное руководство

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• TRNG kickstart may need to be moved to the bootloader in a future release, so that
the RNG can be used earlier.
• The Job Ring driver has a registration and de-registration functions that are not
currently necessary (and may be rewritten in future editions to provide for shutdown
notifications to higher layers.
45.8 Limitations in the Existing Implementation Overview
This chapter describes a prototype of a Keystore Management Interface intended to
provide access to CAAM Secure Memory.
Secure memory provides a controlled and access-protected area where critical system
security parameters can be stored and processed in a running system without bus-level
exposure of clear secrets. Secrets can be imported into and exported from secure
memory, but never exported from secure memory in their cleartext form. Instead, secrets
may be exported from secure memory in a covered form, using keys never visible to the
outside.
This driver, with it's kernel-level API, exposes a basic interface to allow kernel-level
services access to secure memory functionality. It is split into two pieces:
• Keystore Initialization and Maintenance Interfaces
• Keystore Access Interface
The initialization and maintenance services exist to initialize and define the instance of a
keystore interface. Likewise, the access interface allows kernel-level services to use the
API for management of security parameters.
45.9 Initialize Keystore Management Interface
Installs a set of pointers to functions that implement an underlying physical interface to
the keystore subsystem.
In the present release, a default (and hidden) suite of functions implement this interface.
Future implementations of this API may provide for the installation of an alternate
interface. If this occurs, an alternate to this call can be provided.
void sm_init_keystore(struct device *dev);
Arguments:
Limitations in the Existing Implementation Overview
i.MX 6Solo/6DualLite Linux Reference Manual, Rev. L3.0.35_4.1.0, 09/2013
318 Freescale Semiconductor, Inc.